1. Field Of The Invention
This invention relates to plugs for gravel packers, and more particularly, to a plug which may be positioned in a gravel packer by a setting tool and removed from the packer by a retrieving tool for later reuse.
2. Description of the Prior Art
When gravel packing a well it is desirable to minimize the number of trips downhole to operate or install tools and perform the various operations. One ideal method would be to make one trip downhole to set a sump or false bottom packer, then make one more run to set a gravel packer, perform a gravel packing operation, and remove the tool string and operating tool out of the well, leaving the gravel packer ready for production. Another desirable feature would be to enable gravel packing multiple zones within the well bore. Also, in deviated wells or in situations where the packer is set on bottom, it is desirable that the gravel packing operation be carried out without rotation of the tool string.
The gravel packer disclosed here is of the type having an inner mandrel means with a threaded portion therein, and is set by actuation of a pusher sleeve means downwardly with respect to the mandrel means for setting the packer element and slips.
It may become desirable to shut in a well below the gravel packer, such as when production is desired to be carried out at a higher gravel pack location. A plugging apparatus is needed to plug the packer so that such operations may be carried out. Also, it is desirable to plug a lower gravel packer to prevent perforating debris from an upper formation from settling on and plugging the lower gravel packer. The present invention provides a plugging apparatus including a plug which is easily set in a gravel packer of the type described by running the plug into the well bore on a setting tool. The setting tool is disengaged, leaving the plug in the gravel packer. The plugging apparatus of the present invention also provides the desirable characteristic of the plug being retrievable by running a retrieving tool into the well bore to connect to the plug, disengage the plug from the packer and retrieve both the retrieving tool and the plug from the well bore so that production may be again carried out at the packer location.